hello bisesik,
I am looking for a pair of trafos for my DSC dac http://audiodesignguide.com/DSC1/DSC1a.pdf
The ones that I use right now are a pair of chinese that you can find easily 2PCS / 10K:10K permalloy audio isolation transformer, balanced and unbalanced conversion audio isolator-in Transformers from Home Improvement on Aliexpress.com | Alibaba Group .
This is how the manufacturer advise to use them:
And this is how I have them connected in my dac:
It seems those trafos work better when the load is about 5k-7k , so I size R56 according the the preamp input impedance to have that value.
The designer of the dac also recommends Lundahl's LL1527XL/LL1684.
I was wondering if your transformer could be used in my particular application, particularly because they are made with nano-crystalline.
I would appreciate your comments.
As an additional information, for stock transformers Vrms – 1,6V, Zout ~ 900 Ohm (depends on DC resistance primary and secondary winding of transformer, for stock transformers 300 + 300 Ohm).
cheers
I am looking for a pair of trafos for my DSC dac http://audiodesignguide.com/DSC1/DSC1a.pdf
The ones that I use right now are a pair of chinese that you can find easily 2PCS / 10K:10K permalloy audio isolation transformer, balanced and unbalanced conversion audio isolator-in Transformers from Home Improvement on Aliexpress.com | Alibaba Group .
This is how the manufacturer advise to use them:
And this is how I have them connected in my dac:
It seems those trafos work better when the load is about 5k-7k , so I size R56 according the the preamp input impedance to have that value.
The designer of the dac also recommends Lundahl's LL1527XL/LL1684.
I was wondering if your transformer could be used in my particular application, particularly because they are made with nano-crystalline.
I would appreciate your comments.
As an additional information, for stock transformers Vrms – 1,6V, Zout ~ 900 Ohm (depends on DC resistance primary and secondary winding of transformer, for stock transformers 300 + 300 Ohm).
cheers
These ones are actually the ones I bought:
R3 Jiayin 10K:10K permalloy audio transformer pre input cattle single end turn to balance signal isolation-in Transformers from Home Improvement on Aliexpress.com | Alibaba Group
Data from the manufacturer:
The following are the detailed transformer parameters.
Transformer size: 26*25*20mm
Iron core material: nickel containing 85% permalloy
Shielding mode: all directional shielding of copper foil around core
DC resistance: the first stage DC is almost the same, about 304 ohms.
Measured inductance: the first class is about 340H.
Measured frequency response: 20Hz~80KHz -0.2dB
Maximum input current: 15mA
I would be interested also into having the trafos with a lower down frequency instead 20Hz. let´s say 10Hz
R3 Jiayin 10K:10K permalloy audio transformer pre input cattle single end turn to balance signal isolation-in Transformers from Home Improvement on Aliexpress.com | Alibaba Group
Data from the manufacturer:
The following are the detailed transformer parameters.
Transformer size: 26*25*20mm
Iron core material: nickel containing 85% permalloy
Shielding mode: all directional shielding of copper foil around core
DC resistance: the first stage DC is almost the same, about 304 ohms.
Measured inductance: the first class is about 340H.
Measured frequency response: 20Hz~80KHz -0.2dB
Maximum input current: 15mA
I would be interested also into having the trafos with a lower down frequency instead 20Hz. let´s say 10Hz
Hi lindamar.
My transformers 1:0.5+0.5 are suitable to DSC.
Transformer size: D44*24mm
Core: nano-crystalline
Shielding: mu-metall
DCR: ~ 70:35+35 Ohms
Inductance: ~ 320:80+80 H
FR: not worse than 20Hz~80KHz -0.2dB
*
input current: not less than 20mA
*have not tested, but I believe your comment regarding LF capability have no straight relation with statement that -0.2dB@20Hz is not enough - it is very linear FR transformer. Another note - transformers can not stop to work immediately below 20Hz, and there is simply more lost at 10Hz, may be -0.4dB@10Hz in the same measurement condition for that Jiayin trafos, I don't know exactly. It is easier to write compactly for both Low and High Responses: -0.2dB - I believe it is more than needed. But! Transformers made on my type of material in this terms should have less distortion on LF - I suspect it is far more important sonically for LF than deviation within tenths of decibel on LFR.
My transformers 1:0.5+0.5 are suitable to DSC.
Transformer size: D44*24mm
Core: nano-crystalline
Shielding: mu-metall
DCR: ~ 70:35+35 Ohms
Inductance: ~ 320:80+80 H
FR: not worse than 20Hz~80KHz -0.2dB
*input current: not less than 20mA
*have not tested, but I believe your comment regarding LF capability have no straight relation with statement that -0.2dB@20Hz is not enough - it is very linear FR transformer. Another note - transformers can not stop to work immediately below 20Hz, and there is simply more lost at 10Hz, may be -0.4dB@10Hz in the same measurement condition for that Jiayin trafos, I don't know exactly. It is easier to write compactly for both Low and High Responses: -0.2dB - I believe it is more than needed. But! Transformers made on my type of material in this terms should have less distortion on LF - I suspect it is far more important sonically for LF than deviation within tenths of decibel on LFR.
Thank you very much bisesik for responding to my questions, I think I understand your point, very well explained by the way.
Should I pm you for a quote or can you just post it publicly so everyone interested can benefit from that information ?
I am definitely having a pair of those, promise to measure them under load and post oscilloscope results.
Should I pm you for a quote or can you just post it publicly so everyone interested can benefit from that information ?
I am definitely having a pair of those, promise to measure them under load and post oscilloscope results.
Strange, but I can not open Page Redirection at all. I found some pics in google, but can not understand is it possible to do this type of measurement in my SW or should I use some special? And what is the frequency should I use for this measurement? 1kHz sine? I have REW/ARTA/Spectralab/RMAA...
Thx eslei and lemon.
But i didn't found the way to use different soundcards for input and output within "Steps" of Arta. I mean I can't measure on Ian's DAC, because there is no spdif input on it while my soundcard have no I2S output (spdif only). I can measure on chineese board (well known device from smpcb v1.07) via spdif out\line in of my soundcard, but it has strange IMDvsLevel measurement even for stock output on 5532 OpAmp. Too bad totally compared to what I see on picture provided by lemon aboved:
But i didn't found the way to use different soundcards for input and output within "Steps" of Arta. I mean I can't measure on Ian's DAC, because there is no spdif input on it while my soundcard have no I2S output (spdif only). I can measure on chineese board (well known device from smpcb v1.07) via spdif out\line in of my soundcard, but it has strange IMDvsLevel measurement even for stock output on 5532 OpAmp. Too bad totally compared to what I see on picture provided by lemon aboved:
Actually this graph is for 9038q2m without my transformers - it is for stock version on 5532 OpAmp output. SMPCB board sounds much worse compared to Ian's DAC (they are simply from different leagues) that is why I suggest it doesn't matter is there hump on SMPCB or no. If I will find the way to make this test on Ian's DAC, then I will post it, but before this happens, this test gives nothing nor about my transformers nither about DAC and getted sound.
Have you tried the Asio4all as driver?
Usually, you can combined different cards as input and output to one measurement.